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5,882 extensions found in Web Development

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  • CodeCopy

    CodeCopy

    Because copy to clipboard buttons should exist on every code snippet

    Zeno Rocha

    253 users

  • Heading Tag Markup

    Heading Tag Markup

    This extension visual highlights the h-Tag on every page.

    Thomas Czernik

    252 users

  • InspectWP - WordPress Theme & Plugin Detector

    InspectWP - WordPress Theme & Plugin Detector

    InspectWP is a website and WordPress analysis tool which includes a WordPress theme and plugin detector.

    InspectWP

    251 users

  • Easy DNS lookup

    Easy DNS lookup

    Utility to do DNS lookups directly to DNS APIs and display the response in the addon.

    wesinator

    250 users

  • View Page Source

    View Page Source

    Adds the ability to open the page source in a new tab via button (Desktop) or menu (Firefox for Android).

    tnh

    249 users

  • Assets CDN

    Assets CDN

    国内标准Firefox浏览器加速扩展

    saowang

    248 users

  • Postwoman 中文版 - REQRES.CN

    Postwoman 中文版 - REQRES.CN

    为使用 Postwoman Web 版应用程序提供更好的体验。 你没用过 Postwoman 吗？这可是一个惊人的，免费、快速、漂亮的 API 测试请求工具。 请访问 https://reqres.cn/

    xlstudio

    248 users

  • ViewCached

    ViewCached

    Checks the cached version of the site on ViewCached.com

    Giant Anchovy Solutions

    247 users

  • DevTools z-index

    DevTools z-index

    Adds "z-index" panel to DevTools. It shows ranking of elements sorted by z-index value. This would help you to reduce z-index numbers. Stop `z-index: 999999` !!

    Ginpei / ギンペイ

    246 users

  • Dom Tree and CSS Playground

    Dom Tree and CSS Playground

    On ANY web site, easily find/edit the web elements and styles that you need, in real time. Use css playground to micro-view 100's of styles in seconds. NOTE: Use your shortcut key "f" allot.

    Jody Brabec

    245 users

  • Offline Caching

    Offline Caching

    Enable offline caching on any web site or app, allowing for usage even without Internet access.

    octt

    245 users

  • CSS Layout Debugger

    CSS Layout Debugger

    When activated, CSS Layout Debugger applies dynamic backgrounds and outlines to elements on the page in order to assist in layout debugging.

    CSS Layout Debugger

    245 users

  • a11y.css accessibility checker

    a11y.css accessibility checker

    a11y.css provides warnings about possible risks and mistakes that exist in HTML code through a style sheet. This extension also provides several accessibility-related utilities. see https://github.com/ffoodd/a11y.css/tree/webextension for details

    Stephane Deschamps

    243 users

  • Form Hack

    Form Hack

    Show hidden inputs in HTML pages with this simple addon. The addon was created for testing purposes. In the newer version the name or the id of the hidden input is displayed.

    Leonidas Christou

    243 users

  • Interceptor

    Interceptor

    Run web clients without backends by mocking HTTP requests

    Codemancers

    240 users

  • ClickJacking

    ClickJacking

    ClickJacking is a tool developed by Pentester Helper to help website owners determine if their website is vulnerable to clickjacking.

    Pentester Helper

    240 users

  • Switch Direction

    Switch Direction

    Switch Direction in edits, useful for mixed RTL and LTR texts editing.

    ebraminio

    239 users

  • Histogram Viewer

    Histogram Viewer

    Generates the histogram of a selected image.

    David Fichtmueller

    237 users

  • Textern

    Textern

    Edit text in your favourite external editor!

    Jonathan Lebon

    237 users

  • Auto Refresh A

    Auto Refresh A

    Automatically refresh the page every 60 seconds.

    pabloduenas

    236 users

  • Eval Villain

    Eval Villain

    Hook native JavaScript functions before page load to see how a website uses them. Narrow down output based on the appearance of URL and session artifacts, user configured strings/regex, blacklists and more.

    bemodtwz

    235 users

  • phab-test-policy

    phab-test-policy

    Adds Testing Policy UI to Mozilla's Phabricator instance

    nchevobbe

    234 users

  • PixiJS Devtools

    PixiJS Devtools

    Debug games and apps written with PixiJS

    Bob Fanger

    232 users

  • SCTPextension

    SCTPextension

    SCTPextension enables the browser to communicate with the SCTP native application. It so allows a web application to make cryptographic operations (key generation and signatures) on a smart card phisically connected to the host.

    Innovery SpA

    232 users

  • DOMLogger++

    DOMLogger++

    DOMLogger++ allows you to monitor, intercept, and debug JavaScript sinks based on customizable configurations.

    Kévin (Mizu)

    231 users